1/* load.c --- loading object files into the RX simulator.
2
3Copyright (C) 2005, 2007, 2008, 2009, 2010, 2011
4Free Software Foundation, Inc.
5Contributed by Red Hat, Inc.
6
7This file is part of the GNU simulators.
8
9This program is free software; you can redistribute it and/or modify
10it under the terms of the GNU General Public License as published by
11the Free Software Foundation; either version 3 of the License, or
12(at your option) any later version.
13
14This program is distributed in the hope that it will be useful,
15but WITHOUT ANY WARRANTY; without even the implied warranty of
16MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17GNU General Public License for more details.
18
19You should have received a copy of the GNU General Public License
20along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
21
22
23#include "config.h"
24#include <stdlib.h>
25#include <stdio.h>
26#include <string.h>
27
28#include "bfd.h"
29#include "libbfd.h"
30#include "cpu.h"
31#include "mem.h"
32#include "elf/internal.h"
33#include "elf/common.h"
34
35/* A note about endianness and swapping...
36
37   The RX chip is CISC-like in that the opcodes are variable length
38   and are read as a stream of bytes.  However, the chip itself shares
39   the code prefetch block with the data fetch block, so when it's
40   configured for big endian mode, the memory fetched for opcodes is
41   word-swapped.  To compensate for this, the ELF file has the code
42   sections pre-swapped.  Our BFD knows this, and for the convenience
43   of all the other tools, hides this swapping at a very low level.
44   I.e.  it swaps words on the way out and on the way back in.
45
46   Fortunately the iovector routines are unaffected by this, so we
47   can use them to read in the segments directly, without having
48   to worry about byte swapping anything.
49
50   However, our opcode decoder and disassemblers need to swap the data
51   after reading it from the chip memory, just like the chip does.
52   All in all, the code words are swapped four times between the
53   assembler and our decoder.
54
55   If the chip is running in little-endian mode, no swapping is done
56   anywhere.  Note also that the *operands* within opcodes are always
57   encoded in little-endian format.  */
58
59void
60rx_load (bfd *prog)
61{
62  unsigned long highest_addr_loaded = 0;
63  Elf_Internal_Phdr * phdrs;
64  long sizeof_phdrs;
65  int num_headers;
66  int i;
67
68  rx_big_endian = bfd_big_endian (prog);
69
70  /* Note we load by ELF program header not by BFD sections.
71     This is because BFD sections get their information from
72     the ELF section structure, which only includes a VMA value
73     and not an LMA value.  */
74  sizeof_phdrs = bfd_get_elf_phdr_upper_bound (prog);
75  if (sizeof_phdrs == 0)
76    {
77      fprintf (stderr, "Failed to get size of program headers\n");
78      return;
79    }
80  phdrs = malloc (sizeof_phdrs);
81  if (phdrs == NULL)
82    {
83      fprintf (stderr, "Failed allocate memory to hold program headers\n");
84      return;
85    }
86  num_headers = bfd_get_elf_phdrs (prog, phdrs);
87  if (num_headers < 1)
88    {
89      fprintf (stderr, "Failed to read program headers\n");
90      return;
91    }
92
93  for (i = 0; i < num_headers; i++)
94    {
95      Elf_Internal_Phdr * p = phdrs + i;
96      char *buf;
97      bfd_vma size;
98      bfd_vma base;
99      file_ptr offset;
100
101      size = p->p_filesz;
102      if (size <= 0)
103	continue;
104
105      base = p->p_paddr;
106      if (verbose > 1)
107	fprintf (stderr, "[load segment: lma=%08x vma=%08x size=%08x]\n",
108		 (int) base, (int) p->p_vaddr, (int) size);
109
110      buf = malloc (size);
111      if (buf == NULL)
112	{
113	  fprintf (stderr, "Failed to allocate buffer to hold program segment\n");
114	  continue;
115	}
116
117      offset = p->p_offset;
118      if (prog->iovec->bseek (prog, offset, SEEK_SET) != 0)
119	{
120	  fprintf (stderr, "Failed to seek to offset %lx\n", (long) offset);
121	  continue;
122	}
123      if (prog->iovec->bread (prog, buf, size) != size)
124	{
125	  fprintf (stderr, "Failed to read %lx bytes\n", size);
126	  continue;
127	}
128
129      mem_put_blk (base, buf, size);
130      free (buf);
131      if (highest_addr_loaded < base + size - 1 && size >= 4)
132	highest_addr_loaded = base + size - 1;
133    }
134
135  free (phdrs);
136
137  regs.r_pc = prog->start_address;
138
139  if (strcmp (bfd_get_target (prog), "srec") == 0
140      || regs.r_pc == 0)
141    {
142      regs.r_pc = mem_get_si (0xfffffffc);
143      heaptop = heapbottom = 0;
144    }
145
146  reset_decoder ();
147
148  if (verbose > 1)
149    fprintf (stderr, "[start pc=%08x %s]\n",
150	     (unsigned int) regs.r_pc,
151	     rx_big_endian ? "BE" : "LE");
152}
153